Stator of motor having an insulator with lead out guide portions

ABSTRACT

A stator of a motor is provided with a stator core having a plurality of teeth and a plurality of windings wound around teeth of the stator core. The stator also has an insulator that is provided with a plurality of lead-out guide portions that enable lead-out wires of the windings to be drawn out from the tooth winding portions in a state of being close to the tooth winding portions.

CROSS-REFERENCE TO RELATED APPLICATIONS

This U.S. National stage application claims priority under 35 U.S.C.§119(a) to Japanese Patent Application No. 2004-030263 the entirecontents of which are hereby incorporated herein by reference.

TECHNICAL FIELD

The present invention relates to a stator of a motor.

BACKGROUND ART

An electric motor has a stator and a rotor which is rotatably placed inthe stator. Conventionally, there is an electric motor whose stator hasa stator core having a plurality of teeth and windings wound around theteeth of the stator core via insulators. The electric motor of this typeis used as a motor for a compressor of an air conditioner and so on.

Windings are wound around the teeth. At this time, in order to insulatea crossover wire of each winding, an insulating tube, an insulatingsleeve or the like is required. In an attempt to dispense with theinsulating tube and so on, there is known a stator having insulatorsprovided with grooves in which the crossover wires are housed, so thatcontact of the crossover wires of one phase with the crossover wires ofthe other phases is prevented (e.g., see JP 2002-101596 A).

More specifically, insulators on the lead wire side are each formed witha plurality of grooves, and in grooves of an insulator corresponding toa tooth at which a lead wire is raised from a crossover wire of onephase, crossover wires of the same phase but from other teeth arehoused.

However, as shown in FIG. 6, if a winding 52 is wound around a tooth 51,a tooth winding portion 53 is formed. If a concentrated winding methodlike this is adopted, the tooth winding portion 53 takes a spindle shapeand outer surfaces of adjacent tooth winding portions 53 come close toone another. Therefore, a take-out wire (lead-out wire) 54 of one phaseis apt to be brought into contact with the adjacent tooth windingportion 53 of other phases, so that a stable function as a motorcouldn't be exhibited.

SUMMARY OF THE INVENTION

This invention was made in order to solve the above conventionaldrawback, and an object of this invention is to provide a motor statorusing insulators, which prevents a lead-out wire of one phase from beingbrought into contact with windings of other phases and thus has highquality.

A stator of a motor, according to the present invention, comprises astator core having a plurality of teeth; windings, a part of eachwinding being wound around teeth of the stator core via an insulator;and lead-out guide portions provided in the insulator and enablinglead-out wires to be drawn out from corresponding tooth winding portionsof the windings in a state of being close to the corresponding toothwinding portions.

In the stator of a motor with the above construction, since the lead-outguide portions that enable the lead-out wires to be drawn out from thetooth winding portions of the windings in the state of being close tothe tooth winding portions are provided in the insulator, the lead-outwires of one phase are less likely to be brought into contact with theadjacent tooth winding portions of other phases. Therefore, theinsulating property between the adjacent tooth winding portions isimproved, thus making it possible to provide a motor with high quality.Moreover, it is not necessary for the take-out wires (lead-out wires) tobe covered with a protective tube (insulating tube) and so on, thusmaking it possible to improve assembling performance as well as reducecosts.

In one embodiment, each winding includes tooth winding portions, acrossover wire, a neutral wire and a power wire; the winding is woundaround one of two opposed teeth, starting at an end of one tooth windingportion that follows the neutral wire, and the crossover wire directedfrom another end of the tooth winding portion around the one toothtoward the other of the opposed teeth connects to the power wire, and atan end of a tooth winding portion to be around the other tooth thatcontinues from the power wire the winding is wound around the othertooth, and another end of the tooth winding portion around the othertooth is connected to the neutral wire such that a lead-out portion fromthe one tooth winding portion to the other tooth winding portion and alead-out portion from the other tooth winding portion to the neutralwire serve as the lead-out wires.

In the stator of this embodiment, since the lead-out portion from onetooth winding portion to the other tooth winding portion serves as alead-out wire, it is possible to prevent the lead-out wire of one phasefrom being brought into contact with the adjacent tooth winding portionsof other phases. Further, since the lead-out portion from the othertooth winding portion to the neutral wire serves as a lead-out wire, itis possible to prevent the lead-out wire from being brought into contactwith the adjacent tooth winding portions of other phases. By thisarrangement, contact between the different phases can be prevented, anda stable winding operation is enabled. Together with that, the stablywound state can be maintained, so that a motor with high quality isprovided.

In one embodiment, each of the lead-out guide portions comprises agroove provided in the vicinity of a periphery of the correspondingtooth winding portion.

In the stator of the above embodiment, since the lead-out guide portionis formed of a groove provided in the vicinity of the periphery of thetooth winding portion, simplification of the structure can be attempted.Therefore, an improvement in the productivity and a further reduction incosts can be achieved.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a plan view of a motor stator according to the presentinvention;

FIG. 2 is a plan view of an insulator of the stator;

FIG. 3 is a side view of the insulators of the stator in a developedstate;

FIG. 4 is a circuit diagram showing a state of connection of windings ofthe stator;

FIG. 5 is a simplified diagram for showing a winding method for thestator; and

FIG. 6 is a simplified cross sectional view of essential parts of aconventional stator for describing its drawback.

DETAILED DESCRIPTION OF THE INVENTION

Next, a specific embodiment of the motor stator according to the presentinvention will be described below with reference to the drawings. FIG. 1is a simplified view of essential parts of a motor in which the statoris used. The motor is constituted mainly of the stator 1 and a rotor 2which is rotatably fitted in the stator 1. The stator 1 has a statorcore 3 and windings 4 wound on the stator core 3. The stator core 3 hasa core main body 6 formed by stacking a large number of annular-shapedthin plates made of electromagnetic steel and insulators (insulatingmembers) 5, 5 provided on axial end surfaces of the core main body 6(see FIGS. 1 to 3). The stator core 3 is provided with a plurality ofteeth T (six in this case) at a predetermined pitch along acircumferential direction thereof. The windings 4 are wound on therespective teeth T. At this time, slots 15 are formed between adjacentteeth T along the circumferential direction. There are six slots 15 inthis case, i.e., from a first slot 15 a to a sixth slot 15 f. In FIG. 1,reference numeral 20 denotes a lead wire in which U-, V-, and W-phasepower wires are bundled.

The rotor 2 has a rotor core 7 and a plurality of magnets (not shown)embedded in the rotor core 7. A shaft (not shown) is inserted throughand fixed by an axial hole of the rotor core 7. In this case, the rotorcore 7 is formed by stacking a large number of annular-shaped thinplates made of electromagnetic steel.

As shown in FIG. 2, each of the insulators 5 includes a peripheral wall8, a plurality of radially internally protruding portions 9 protrudingfrom the peripheral wall 8, and raised portions 10 provided at an endedge of the radially internally protruding portions 9 to face theperipheral wall 8. The radially internally protruding portions 9 arearranged circumferentially at a predetermined pitch (at a pitch of 60°).One insulator 5 (5 a) is fitted on one axial end surface of the corebody 6, while the other insulator 5 (5 b) is fitted on the other endsurface of the core body 6.

The windings 4 consist of a U-phase winding 4 a, a V-phase winding 4 band a W-phase winding 4 c as shown in FIG. 4. The U-phase winding 4 ahas a first magnetic pole portion U1 and a second magnetic pole portionU2; the V-phase winding 4 b has a first magnetic pole portion V1 and asecond magnetic pole portion V2; and the W-phase winding 4 c has a firstmagnetic pole portion W1 and a second magnetic pole portion W2. TheU-phase winding 4 a, the V-phase winding 4 b and the W-phase winding 4 care connected to one another via a neutral point N. At this time, asshown in FIG. 1, the first magnetic pole portion U1 and the secondmagnetic pole portion U2 of the U-phase winding 4 a are placed in such amanner as to be symmetrical with each other with respect to a centralaxis of the stator core 3 so that they are opposite to each other; thefirst magnetic pole portion V1 and the second magnetic pole portion V2of the V-phase winding 4 b are placed in such a manner as to besymmetrical with each other with respect to the central axis of thestator core 3 so that they are opposite to each other; and the firstmagnetic pole portion W1 and the second magnetic pole portion W2 of theW-phase winding 4 c are placed in such a manner as to be symmetricalwith each other with respect to the central axis of the stator core 3 sothat they are opposite to each other.

The winding method will be described in detail regarding the U-phasewinding 4 a. As shown in FIG. 5, a part following a neutral wire 30 ofthe winding is wound around one of the opposed teeth T until after atooth winding portion 11 a serving as the second magnetic pole portionU2 is provided. A crossover wire 31 to the other tooth T is extended toserve as a power wire 29. Then, a part following the power wire 29 ofthe winding is wound around the other tooth T until after a toothwinding portion 11 b serving as the first magnetic pole portion U1 isprovided. A winding end at the other tooth T is drawn out toward theneutral wire 30 so as to be connected to the neutral wire. That is, theneutral wire 30 a on the winding start side of the tooth winding portion11 a serving as the second magnetic pole portion U2 is connected to aneutral wire 30 b on the winding end side of the tooth winding portion11 b serving as the first magnetic pole portion U1 via the neutral pointN. The same winding method as that of the U-phase winding 4 a is appliedto the other V-phase winding 4 b and W-phase winding 4 c. Therefore, thesecond magnetic pole portion U2, V2, W2 of each winding 4 a, 4 b, 4 chas a lead-out portion 32 drawn out to the first magnetic pole portionU1, V1, W1, and the first magnetic pole portion U1, V1, W1 has alead-out portion 33 drawn out to the neutral wire 30 (30 b).

One insulator 5 a is provided with lead-out guide portions 13, whichenable lead-out wires 12 to be drawn out from their respective toothwinding portions 11 in a state of being close to the respective toothwinding portions 11. In this case, the lead-out guide portions 13 can beeach constructed of a groove 14 provided in the vicinity of theperiphery of the corresponding tooth winding portion 11. That is, asshown in FIGS. 2 and 3, the peripheral wall 8 has a plurality ofsub-walls 16 corresponding to slots 15 (namely, gaps defined between thecircumferentially adjacent teeth T and T). Of the slots, a first slot 15a corresponds to a first sub-wall 16 a, a second slot 15 b correspondsto a second sub-wall 16 b, a third slot 15 c corresponds to a thirdsub-wall 16 c, a fourth slot 15 d corresponds to a fourth sub-wall 16 d,a fifth slot 15 e corresponds to a fifth sub-wall 16 e, and a sixth slot16 f corresponds to a sixth sub-wall 16 f. The grooves 14 are providedin the sub-walls 16 a, 16 b, and 16 c, respectively. Each groove 14 isplaced in a position nearer the corresponding tooth winding portion 11(self-wound portion), from which the lead-out wire 12 is drawn out, inrelation to the center O of the slot 15. The groove 14 consists of anaxially extending main part 18 and notch portions 19, 19 at an open endof the main part 18.

In this case, as shown in FIG. 3, for example, the groove 14 formed inthe first sub-wall 16 a is shifted by a predetermined angle θ1 (e.g.,about five degrees) relative to the center O of the first slot 15 a in acounterclockwise direction. The groove 14 formed in the second sub-wall16 b is shifted by the predetermine angle θ1 (e.g., about five degrees)relative to the center O of the second slot 15 b in the counterclockwisedirection, and the groove 14 formed in the third sub-wall 16 c isshifted by the predetermine angle θ1 (e.g., about five degrees) relativeto the center O of the third slot 15 c in the counterclockwisedirection.

The other insulator 5 b is also provided with sub-walls 17, of which afirst sub-wall 17 a corresponds to the first slot 15 a; a secondsub-wall 17 b corresponds to the second slot 15 b; a third sub-wall 17 ccorresponds to the third slot 15 c, a fourth sub-wall 17 d correspondsto the fourth slot 15 d, a fifth sub-wall 17 e corresponds to the fifthslot 15 e, and a sixth sub-wall 17 f corresponds to the sixth slot 15 f.Also, the sub-walls 17 d, 17 e, 17 f are each provided with the groove14 serving as the lead-out guide portion 13.

In this case, for example, the groove 14 formed in the fourth sub-wall17 d, the groove 14 formed in the fifth sub-wall 17 e, and the groove 14formed in the sixth sub-wall 16 f are each shifted by a predetermineangle (e.g., about five degrees) relative to the center O of thecorresponding slots 15 in the clockwise direction. The lead-out portion32, which is drawn out from the U-phase second magnetic pole portion U2to the U-phase first magnetic pole portion U1, serves as the lead-outwire 12, and is drawn out via the groove 14 formed in the fourthsub-wall 17 d of the insulator 5 b. Also, the lead-out portion 33, whichis drawn out from the U-phase first magnetic pole portion U1 to theneutral wire 30 b, serves as the lead-out wire 12, and is drawn out viathe groove 14 formed in the first sub-wall 16 a of the insulator 5 a.Similarly, the lead-out portion 32 that is drawn out from the V-phasesecond magnetic pole portion V2 to the V-phase first magnetic poleportion V1 serves as the lead-out wire 12, and is drawn out via thegroove 14 formed in the fifth sub-wall 17 e of the insulator 5 b, andthe lead-out portion 33 that is drawn out from the V-phase firstmagnetic pole portion V1 to the neutral wire 30 b serves as the lead-outwire 12 and is drawn out via the groove 14 formed in the second sub-wall16 b of the insulator 5 a. Also, the lead-out portion 32 that is drawnout from the W-phase second magnetic pole portion W2 to the W-phasefirst magnetic pole portion W1 serves as the lead-out wire 12, and isdrawn out via the groove 14 formed in the sixth sub-wall 17 f of theinsulator 5 b, and the lead-out portion 33 that is drawn out from theW-phase first magnetic pole portion W1 to the neutral wire 30 b servesas the lead-out wire 12, and is drawn out via the groove 14 formed inthe third sub-wall 16 c of the insulator 5 a.

This motor (which is of permanent magnet type) is used as, for example,a motor for a compressor of an air conditioner. The compressor includesa casing, which is a sealed container, a compressor elements part housedin the lower side of the sealed container, and a motor elements parthoused in the upper side of the sealed container. The permanent magnettype motor is used for the motor elements part. Therefore, a shaft thatis inserted through and fixed by the axial hole of the rotor 2 is acrankshaft for the compressor elements part, and the crankshaft issupported by a supporting member within the sealed container.

In the stator 1 constituted as described above, the lead-out wire 12from the tooth winding portion 11 is fitted (engaged) in the groove 14close to the tooth winding portion 11, whereby the lead-out wire 12 canbe drawn out in a state of being close to the tooth winding portion 11.That is, the insulator 5 is provided with the lead-out guide portions 13that enable the lead-out wires 12 to be drawn out from the tooth windingportions 11 of the windings 4 in a state of being close to the toothwinding portions 11. This makes the lead-out wire 12 of one phase lesslikely to be brought into contact with the tooth winding portions 11 ofother phases, and the insulation between the adjacent tooth windingportions 11, 11 is improved. Thus, a motor with high quality can beprovided. Moreover, it is not necessary for the take-out wires (lead-outwires) 12 to be covered with a protective tube (insulating tube) and soon, thus making it possible to improve assembling performance as well asreduce costs. In particular, in the stator in which the winding 4 iswound from its neutral wire 30 around one of the opposed teeth T, andthe crossover wire 31 from the one tooth T to the other tooth T leads tothe power wire 29, from which the winding 4 is wound around the othertooth T, and the winding end of the other tooth T is drawn out towardthe neutral wire 30 and connected to the neutral wire 30, and thelead-out portion 32 from one tooth winding portion 11 to the other toothwinding portion 11 and the lead-out portion 33 from the other toothwinding portion 11 to the neutral wire 30 (30 b) serve as the lead-outwires 12, it is possible to prevent the lead-out wire 12 of one phaseextending from one tooth winding portion 11 to the other tooth windingportion 11 from being brought into contact with the adjacent toothwinding portions 11 of other phases. Also, it is possible to prevent thelead-out wire 12 extending from the other tooth winding portion 11 tothe neutral wire 30 from being brought into contact with the adjacenttooth winding portions 11 of other phases, too. By this arrangement, acontact between the different phases can be prevented, and a stablewinding operation is enabled, and also, since the stably wound state canbe maintained, a motor with high quality can be provided.

Since the lead-out guide portion 13 can be formed of the groove 14provided in the vicinity of the periphery of the tooth winding portion11, simplification of the structure can be attempted. For that reason,an improvement in the productivity and a further reduction in the costscan be achieved. Also, the groove 14 has the notch portions 19, 19 atthe open end of the main part 18, which is advantageous in that thelead-out wire 12 is easily engaged in the groove 14.

Embodiments of the invention being thus described, it will be obviousthat the preset invention is not limited to those embodiments, but thatsame may be varied in many ways within the scope of the followingclaims. For example, the position of the groove 14 constituting thelead-out guide portion 13 is not limited to the shown one as far as thegroove position allows the lead-out wire 12 to be drawn out in thevicinity of the tooth winding portion 11. Further, dimensions of thegroove 14 such as a width and a depth can be set as desired as far asthe lead-out wire 12 can be engaged with (fitted in) the groove 14.Furthermore, the number of the phases and the number of the poles may bechanged, and the lead-out guide portion 13 may also be constituted of ahole or the like in the insulator.

1. A stator of motor comprising: a stator core having a plurality ofteeth, said plurality of teeth including at least a first tooth and asecond tooth radially opposed to each other; an insulator, the insulatorincluding a pair of insulating members provided on axially oppositesides of the stator core; and a winding with part of the winding beingwound about the first and second teeth of the stator core, with theinsulator disposed between the stator core and the winding, said windingincluding a first tooth winding portion and a second tooth windingportion wound about the first tooth and the second tooth, respectively,a first neutral wire connected to an end of the first tooth windingportion, a first lead-out wire extending from another end of the firsttooth winding portion, a crossover wire having one end connected to thefirst lead-out wire and extending to a position which is radiallyoutside of the second tooth winding portion at which the crossover wireis on the second tooth winding portion, a power wire having a firstportion with an end connected to another end of the crossover wire, anda second portion with an end connected to another end of the firstportion and another end connected to an end of the second tooth windingportion, a second lead-out wire extending from another end of the secondtooth winding portion, and a second neutral wire connected to the secondlead-out wire, the insulator including a plurality of lead-out guideportions with each of the first and second lead-out wires being drawnout through one of the lead-out guide portions from a corresponding oneof the tooth winding portions of the winding, each of the insulatingmembers including a peripheral wall and a plurality of radiallyinternally protruding portions protruding from the peripheral wall, theperipheral wall of each insulating member having a plurality ofsub-walls in one-to-one correspondence to slots defined between theteeth of the stator core, and a lead-out guide portion corresponding tothe first tooth winding portion of the winding being provided in acorresponding one of the sub-walls of one insulating member, and alead-out guide portion corresponding to the second tooth winding portionof the winding being provided in a corresponding one of the sub-walls ofthe other insulating member.
 2. The stator according to claim 1, whereinthe lead out guide portions are aligned with circumferential edgeportions of the teeth as viewed along radial directions of the lead outguide portions.
 3. The stator according to claim 2, wherein the lead outguide portions have radially extending center lines that are offset fromcenters of slots formed between the teeth and the parts of the windingwound around the teeth.
 4. The stator according to claim 3, wherein theradially extending center lines are offset about 5 degrees from centersof slots formed between the teeth and the parts of the winding woundaround the teeth.